Dentifrice compositions comprising tin ions

ABSTRACT

A dentifrice composition with tin, calcium, and a pH of greater than 7. A dentifrice composition with tin, fluoride, calcium abrasive, water, and a pH of greater than 7. Dentifrice compositions with a high tin ion availability. Dentifrice compositions comprising stannous fluoride and/or stannous chloride in combination with calcium carbonate.

FIELD OF THE INVENTION

The present invention relates to compositions comprising tin andcalcium. The present invention also relates to compositions comprisingstannous fluoride and calcium carbonate.

BACKGROUND OF THE INVENTION

Sources of tin ions, such as stannous fluoride, are added to dentifricecompositions to deliver antimicrobial and antisensitivity benefits.However, tin ion sources can be difficult to incorporate into dentifricecompositions due to (i) the reactivity between tin ions and otherdentifrice components, such as silica, and (ii) the formation ofinsoluble tin compounds at particular pH conditions. Thus, theincorporation of tin Ions into dentifrice compositions is only possibleby minimizing interactions between tin ions and key dentifricecomponents during storage to maximize tin ion availability forreactivity with oral cavity surfaces, such as enamel, dentine, gums,plaque, and bacteria.

The chemical instability in solution of tin ions can be mitigated bylowering the pH of the solution, providing anionic chelants, such asanions of organic acids, or providing polymeric chelants, such aspolyphosphates or polycarboxylates. Some of these chelants can alsoprevent tin ion interactions with the surface of silica molecules byinstead binding directly to the tin ions. However, strong chelant-tinion interactions can also be detrimental to tin ion availability if thechelant-tin ion interactions are stronger than binding affinity betweentin ions and intra oral surfaces, such tin ion delivery is aprerequisite for performance against diseases of the oral cavity such asplaque, gingivitis, malodor, caries, sensitivity, and dental erosionetc. Thus, even chelant selection must be balanced with the overalldentifrice formulation to maximize tin ion availability.

Additionally, the selected abrasive system can influence the tin ionavailability. For example, calcium abrasives, such as calciumpyrophosphate and dicalcium phosphate, can interact with tin ionsgenerated from stannous fluoride to result in a loss of up to 90% of theavailable tin ions over the life of a dentifrice. Switching from acalcium phosphate-based abrasive to a silica abrasive system can improvethe amount of available tin ions, but will still result in only up to50% available tin ions due to surface interactions between the tin ionand the silica abrasive. A 50% tin ion availability is still significantenough to require supplemental sources of tin ions to be added, such asstannous chloride, to compensate for the reactivity between the tin ionsand the surface of the silica abrasive. Other approaches includehydrophobic modification of the silica surface, heat treating the silicato remove reactive surface hydroxyl functional groups or formulating thedentifrice with minimal or no water to prevent reactivity between theabrasive and free tin ions. However, each of these strategies tomitigate the loss of free tin ions in solution, and be available tointeract with the oral cavity, results in higher costs, limitingcommercial viability of these approaches. Therefore, there is a need fora dentifrice composition that provides a source of available tin ions atan affordable cost.

SUMMARY OF THE INVENTION

This summary is provided to introduce a selection of concepts in asimplified form that are further described below in the detaileddescription. This summary is not intended to identify required oressential features of the claimed subject matter. Nor is this summaryintended to be used to limit the scope of the claimed subject matter.

Disclosed herein is a dentifrice composition comprising from about0.0025% to about 5%, by weight of the dentifrice composition, of a tinion source, from about 10% to about 50%, by weight of the dentifricecomposition, of a calcium abrasive, and less than about 5%, by weight ofthe dentifrice composition, of water, wherein the dentifrice compositionhas a pH of greater than 7.

Disclosed herein is a dentifrice composition comprising from about0.0025% to about 5%, by weight of the dentifrice composition, of a tinion source, from about 0.0025% to about 5%, by weight of the dentifricecomposition, of a fluoride ion source, the fluoride ion sourcecomprising sodium fluoride, sodium monofluorophosphate, amine fluoride,or combinations thereof, from about 10% to about 50%, by weight of thedentifrice composition, of calcium carbonate, and from about 10% toabout 45%, by weight of the dentifrice composition, of water, whereinthe dentifrice composition has a pH of greater than 7.

Disclosed herein is a dentifrice composition comprising from about 0.01%to about 5%, by weight of the dentifrice composition, of a tin ionsource, from about 10% to about 50%, by weight of the dentifricecomposition, of calcium carbonate, and from about 5% to about 75%, byweight of the dentifrice composition, of water, wherein the dentifricecomposition has a pH of greater than 7 and wherein the dentifricecomposition has about 70% or greater of available tin ions after threemonths at 40° C.

DETAILED DESCRIPTION OF THE INVENTION

The present invention is directed to dentifrice compositions comprisinga tin ion source and a calcium abrasive. Additionally, the presentinvention is directed to dentifrice compositions comprising stannousfluoride and calcium carbonate.

While the formation of CaF₂ is desired in the oral cavity, manydentifrice formulations do not employ calcium ions and fluoride ions inaqueous dentifrice compositions because CaF₂ can precipitate out ofsolution during storage, thereby eliminating any benefit derived fromcalcium or fluoride ions. For example, calcium carbonate (CaCO₃) is anabrasive of choice to minimize dentifrice formulation costs. However,due to the incompatibility between free fluoride and calcium ions,almost all CaCO₃ based formulations use sodium monofluorophosphate saltas a less reactive fluoride source.

In addition to the possibility of premature CaF₂ formations, using CaCO₃in combination with a tin ion source can also raise the pH of thedentifrice composition, which can lead to the precipitation of Sn(OH)₂out of the dentifrice composition, thereby eliminating any benefitderived from free tin ions.

As such, dentifrice compositions comprising a tin ion source and acalcium abrasive are typically not expected to be compatible due to thepossibility for the formation of CaF₂ and Sn(OH)₂, which can precipitateout of the dentifrice composition. Unexpectedly, and as describedherein, stable dentifrice compositions comprising a tin ion source and acalcium abrasive at a pH of greater than 7 has been found to be shelfstable with minimal or no formation of CaF₂ and/or Sn(OH)₂.Additionally, the stable dentifrice compositions have been found to havegreater than about 80% of available tin ions and/or greater than about80% of available fluoride ions even after several months. Withoutwishing to be bound by theory, it is believed that when dentifricecompositions comprising a tin ion source and a calcium abrasive areproperly formulated, the amount of available tin ions can be increasedrelative to dentifrice compositions comprising a tin ion source and asilica abrasive. Additionally, the dentifrice compositions describedherein would comprise components with lower costs to increase thecommercial viability of such an approach.

While the specification concludes with claims particularly pointing outand distinctly claiming the invention, it is believed that the presentinvention will be better understood from the following description.

Definitions

To define more clearly the terms used herein, the following definitionsare provided. Unless otherwise indicated, the following definitions areapplicable to this disclosure. If a term is used in this disclosure butis not specifically defined herein, the definition from the IUPACCompendium of Chemical Terminology, 2nd Ed (1997), can be applied, aslong as that definition does not conflict with any other disclosure ordefinition applied herein, or render indefinite or non-enabled any claimto which that definition is applied.

The term “oral care composition”, as used herein, includes a product,which in the ordinary course of usage, is not intentionally swallowedfor purposes of systemic administration of particular therapeuticagents, but is rather retained in the oral cavity for a time sufficientto contact dental surfaces or oral tissues. Examples of oral carecompositions include dentifrice, tooth gel, subgingival gel, mouthrinse, mousse, foam, mouth spray, lozenge, chewable tablet, chewing gum,tooth whitening strips, floss and floss coatings, breath fresheningdissolvable strips, or denture care or adhesive product. The oral carecomposition may also be incorporated onto strips or films for directapplication or attachment to oral surfaces.

The term “dentifrice composition”, as used herein, includes tooth orsubgingival-paste, gel, or liquid formulations unless otherwisespecified. The dentifrice composition may be a single-phase compositionor may be a combination of two or more separate dentifrice compositions.The dentifrice composition may be in any desired form, such as deepstriped, surface striped, multilayered, having a gel surrounding apaste, or any combination thereof. Each dentifrice composition in adentifrice comprising two or more separate dentifrice compositions maybe contained in a physically separated compartment of a dispenser anddispensed side-by-side.

“Active and other ingredients” useful herein may be categorized ordescribed herein by their cosmetic and/or therapeutic benefit or theirpostulated mode of action or function. However, it is to be understoodthat the active and other ingredients useful herein can, in someinstances, provide more than one cosmetic and/or therapeutic benefit orfunction or operate via more than one mode of action. Therefore,classifications herein are made for the sake of convenience and are notintended to limit an ingredient to the particularly stated function(s)or activities listed.

The term “orally acceptable carrier” comprises one or more compatiblesolid or liquid excipients or diluents which are suitable for topicaloral administration. By “compatible,” as used herein, is meant that thecomponents of the composition are capable of being commingled withoutinteraction in a manner which would substantially reduce thecomposition's stability and/or efficacy. The carriers or excipients ofthe present invention can include the usual and conventional componentsof mouthwashes or mouth rinses, as more fully described hereinafter:Mouthwash or mouth rinse carrier materials typically include, but arenot limited to one or more of water, alcohol, humectants, surfactants,and acceptance improving agents, such as flavoring, sweetening, coloringand/or cooling agents.

The term “substantially free” as used herein refers to the presence ofno more than 0.05%, preferably no more than 0.01%, and more preferablyno more than 0.001%, of an indicated material in a composition, by totalweight of such composition.

The term “essentially free” as used herein means that the indicatedmaterial is not deliberately added to the composition, or preferably notpresent at analytically detectable levels. It is meant to includecompositions whereby the indicated material is present only as animpurity of one of the other materials deliberately added.

While compositions and methods are described herein in terms of“comprising” various components or steps, the compositions and methodscan also “consist essentially of” or “consist of” the various componentsor steps, unless stated otherwise.

As used herein, the word “or” when used as a connector of two or moreelements is meant to include the elements individually and incombination; for example, X or Y, means X or Y or both.

As used herein, the articles “a” and “an” are understood to mean one ormore of the material that is claimed or described, for example, “an oralcare composition” or “a bleaching agent.”

All measurements referred to herein are made at about 23° C. (i.e. roomtemperature) unless otherwise specified.

Generally, groups of elements are indicated using the numbering schemeindicated in the version of the periodic table of elements published inChemical and Engineering News, 63(5), 27, 1985. In some instances, agroup of elements can be indicated using a common name assigned to thegroup; for example, alkali metals for Group 1 elements, alkaline earthmetals for Group 2 elements, and so forth.

Several types of ranges are disclosed in the present invention. When arange of any type is disclosed or claimed, the intent is to disclose orclaim individually each possible number that such a range couldreasonably encompass, including end points of the range as well as anysub-ranges and combinations of sub-ranges encompassed therein.

The term “about” means that amounts, sizes, formulations, parameters,and other quantities and characteristics are not and need not be exact,but can be approximate and/or larger or smaller, as desired, reflectingtolerances, conversion factors, rounding off, measurement errors, andthe like, and other factors known to those of skill in the art. Ingeneral, an amount, size, formulation, parameter or other quantity orcharacteristic is “about” or “approximate” whether or not expresslystated to be such. The term “about” also encompasses amounts that differdue to different equilibrium conditions for a composition resulting froma particular initial mixture. Whether or not modified by the term“about,” the claims include equivalents to the quantities. The term“about” can mean within 10% of the reported numerical value, preferablywithin 5% of the reported numerical value.

The dentifrice composition can be in any suitable form, such as a solid,liquid, powder, paste, or combinations thereof. The oral carecomposition can be dentifrice, tooth gel, subgingival gel, mouth rinse,mousse, foam, mouth spray, lozenge, chewable tablet, chewing gum, toothwhitening strips, floss and floss coatings, breath fresheningdissolvable strips, or denture care or adhesive product. The componentsof the dentifrice composition can be incorporated into a film, a strip,a foam, or a fiber-based dentifrice composition. The dentifricecomposition can include a variety of active and inactive ingredients,such as, for example, but not limited to a tin ion source, a calciumabrasive, water, a fluoride source, zinc ion source, one or morepolyphosphates, humectants, surfactants, other ingredients, and thelike, as well as any combination thereof, as described below.

Tin

The dentifrice composition of the present invention comprise tin. Thetin can be provided by a tin ion source. The tin ion source can be anysuitable compound that can provide tin ions in a dentifrice compositionand/or deliver tin ions to the oral cavity when the dentifricecomposition is applied to the oral cavity. The tin ion source cancomprise one or more tin containing compounds, such as stannousfluoride, stannous chloride, stannous bromide, stannous iodide, stannousoxide, stannous oxalate, stannous sulfate, stannous sulfide, stannicfluoride, stannic chloride, stannic bromide, stannic iodide, stannicsulfide, and/or mixtures thereof. Preferably, the tin ion source cancomprise stannous fluoride, stannous chloride, and/or mixture thereof.

The dentifrice composition can comprise from about 0.0025% to about 5%,from about 0.2% to about 1%, from about 0.5% to about 1.5%, or fromabout 0.3% to about 0.6%, by weight of the dentifrice composition, of atin ion source.

Calcium Abrasive

The dentifrice composition of the present invention comprises calcium.The calcium can be provided by a calcium abrasive. Abrasives can beadded to dentifrice formulations to help remove surface stains fromteeth. The calcium abrasive can be any suitable abrasive compound thatcan provide calcium ions in a dentifrice composition and/or delivercalcium ions to the oral cavity when the dentifrice composition isapplied to the oral cavity.

The dentifrice composition can comprise from about 5% to about 70%, fromabout 10% to about 50%, from about 10% to about 60%, from about 20% toabout 50%, from about 25% to about 40%, or from about 1% to about 50% ofa calcium abrasive. The calcium abrasive can comprise one or morecalcium abrasive compounds, such as calcium carbonate, precipitatedcalcium carbonate (PCC), ground calcium carbonate (GCC), chalk,dicalcium phosphate, calcium pyrophosphate, and/or mixtures thereof.

The dentifrice composition can comprise an additional non-calciumabrasive, such as bentonite, silica gel (by itself, and of anystructure), precipitated silica, amorphous precipitated silica (byitself, and of any structure as well), hydrated silica, perlite,titanium dioxide, alumina, hydrated alumina, calcined alumina, aluminumsilicate, insoluble sodium metaphosphate, insoluble potassiummetaphosphate, insoluble magnesium carbonate, zirconium silicate,particulate thermosetting resins and other suitable abrasive materials.Such materials can be introduced into the dentifrice compositions totailor the polishing characteristics of the target dentifriceformulation. The dentifrice composition can comprise from about 5% toabout 70%, from about 10% to about 50%, from about 10% to about 60%,from about 20% to about 50%, from about 25% to about 40%, or from about1% to about 50%, by weight of the dentifrice composition, of thenon-calcium abrasive

Alternatively, the dentifrice composition can be substantially free of,essentially free of, or free of silica, alumina, or any othernon-calcium abrasive. The dentifrice composition can comprise less thanabout 5%, less than about 1%, less than about 0.5%, less than about0.1%, or 0% of a non-calcium abrasive, such as silica and/or alumina.

Polyol

The oral care compositions of the present invention can comprise polyol.A polyol is an organic compound with more than one hydroxyl functionalgroups. The polyol can be any suitable compound that can weaklyassociate, interact, or bond to tin ions while the oral care compositionis stored prior to use. The polyol can be a sugar alcohol, amonosaccharide, a disaccharide, a polysaccharide, or a non-reducingsugar. Sugar alcohols are a class of polyols that can be obtainedthrough the hydrogenation of sugar compounds with the formula(CHOH)_(n)H₂, where n=4-6. Preferably, n is 5 and/or 6 because thesecompounds have been shown to unexpectedly interact with tin ion sourcesto create soluble complexes, as described herein.

The polyol can be glycerin, erythritol, xylitol, sorbitol, mannitol,butylene glycol, lactitol, galactitol, and/or combinations thereof.Preferably, the polyol can be a sugar alcohol with the formula(CHOH)_(n)H₂, where n=4-6. More preferably, the polyol can be a sugaralcohol with the formula (CHOH)_(n)H₂, where n=5 and/or 6. Even morepreferably, the polyol can be xylitol, sorbitol, galactitol, and/ormixtures thereof.

The oral care composition can comprise 0.01% to about 70%, from about 5%to about 70%, from about 5% to about 50%, from about 10% to about 60%,or from about 20% to about 80%, by weight of the oral care composition,of a polyol.

The oral care composition can also comprise an additional humectant,have low levels of an additional humectant, be substantially free of,essentially free, or be free of an additional humectant. Humectants, ingeneral, serve to add body or “mouth texture” to an oral carecomposition or dentifrice as well as preventing the oral carecomposition from drying out. Suitable humectants include polyethyleneglycol (at a variety of different molecular weights), propylene glycol,glycerin, erythritol, xylitol, sorbitol, mannitol, butylene glycol,lactitol, hydrogenated starch hydrolysates, and/or mixtures thereof. Theoral care composition can comprise a polyol and an additional humectant,such as xylitol to interact with the tin ion source and glycerin toprevent the oral care composition from drying out during storage or addbody to the oral care composition. The oral care composition can also befree of an additional humectant because the polyol can serve as both thepolyol and the additional humectant, such as when the polyol is xylitol,sorbitol, or combinations thereof.

The oral care composition can comprise one or more humectants each at alevel of from about 0.01% to about 70%, from about 5% to about 50%, fromabout 10% to about 60%, or from about 20% to about 80%, by weight of theoral care composition.

Water

The dentifrice composition of the present invention can be anhydrous, alow water formulation, or a high water formulation. In total, the oralcare composition can comprise from 0% to about 99%, from about 5% toabout 75%, about 20% or greater, about 30% or greater, or about 50% orgreater by weight of the composition, of water. Preferably, the water isUSP water.

In a high water dentifrice formulation, the dentifrice compositioncomprises from about 45% to about 75%, by weight of the composition, ofwater. The high water dentifrice composition can comprise from about 45%to about 65%, from about 45% to about 55%, or from about 46% to about54%, by weight of the composition, of water. The water may be added tothe high water dentifrice formulation and/or may come into thecomposition from the inclusion of other ingredients.

In a low water dentifrice formulation, the dentifrice compositioncomprises from about 5% to about 45%, by weight of the composition, ofwater. The low water dentifrice composition can comprise from about 5%to about 35%, from about 10% to about 25%, or from about 20% to about25%, by weight of the composition, of water. The water may be added tothe low water dentifrice formulation and/or may come into thecomposition from the inclusion of other ingredients.

In an anhydrous dentifrice formulation, the dentifrice compositioncomprises less than about 10%, by weight of the composition, of water.The anhydrous dentifrice composition comprises less than about 5%, lessthan about 1%, or 0%, by weight of the composition, of water. The watermay be added to the anhydrous formulation and/or may come into thedentifrice composition from the inclusion of other ingredients.

The dentifrice composition can also comprise other orally acceptablecarrier materials, such as alcohol, humectants, polymers, surfactants,and acceptance improving agents, such as flavoring, sweetening, coloringand/or cooling agents.

pH

The dentifrice composition can comprise one or more buffering agents.Buffering agents, as used herein, refer to agents that can be used toadjust the slurry pH of the dentifrice compositions to a range ofgreater than 7, from greater than 7 to about 14, about 7.5 or greater,about 8 or greater, from about 7.5 to 10, greater than 7 to about 10, orfrom about 8 to about 10. The buffering agents include alkali metalhydroxides, carbonates, sesquicarbonates, borates, silicates,phosphates, imidazole, and mixtures thereof. Specific buffering agentsinclude monosodium phosphate, trisodium phosphate, sodium hydroxide,potassium hydroxide, alkali metal carbonate salts, sodium carbonate,imidazole, pyrophosphate salts, citric acid, and sodium citrate. Thedentifrice composition can comprise one or more buffering agents each ata level of from about 0.1% to about 30%, from about 1% to about 10%, orfrom about 1.5% to about 3%, by weight of the present composition.

Zinc

The dentifrice composition can comprise zinc. The zinc can be providedby a zinc ion source. The zinc ion source can comprise one or more zinccontaining compounds, such as zinc fluoride, zinc lactate, zinc oxide,zinc phosphate, zinc chloride, zinc acetate, zinc hexafluorozirconate,zinc sulfate, zinc tartrate, zinc gluconate, zinc citrate, zinc malate,zinc glycinate, zinc pyrophosphate, zinc metaphosphate, zinc oxalate,and/or zinc carbonate.

The zinc ion source may be present in the total dentifrice compositionat an amount of from about 0.01% to about 5%, from about 0.2% to about1%, from about 0.5% to about 1.5%, or from about 0.3% to about 0.6%, byweight of the dentifrice composition.

Fluoride

The dentifrice composition can comprise fluoride. The fluoride can beprovided by a fluoride ion source. The fluoride ion source can compriseone or more fluoride containing compounds, such as stannous fluoride,sodium fluoride, potassium fluoride, amine fluoride, sodiummonofluorophosphate, zinc fluoride, and/or mixtures thereof.

The fluoride ion source and the tin ion source can be the same compound,such as for example, stannous fluoride, which can generate tin ions andfluoride ions. Additionally, the fluoride ion source and the tin ionsource can be separate compounds, such as when the tin ion source isstannous chloride and the fluoride ion source is sodiummonofluorophosphate or sodium fluoride.

The fluoride ion source and the zinc ion source can be the samecompound, such as for example, zinc fluoride, which can generate zincions and fluoride ions. Additionally, the fluoride ion source and thezinc ion source can be separate compounds, such as when the zinc ionsource is zinc phosphate and the fluoride ion source is stannousfluoride.

The dentifrice composition can comprise a fluoride ion source capable ofproviding from about 50 ppm to about 5000 ppm, and preferably from about500 ppm to about 3000 ppm of free fluoride ions. To deliver the desiredamount of fluoride ions, the fluoride ion source may be present in thetotal dentifrice composition at an amount of from about 0.0025% to about5%, from about 0.2% to about 1%, from about 0.5% to about 1.5%, or fromabout 0.3% to about 0.6%, by weight of the dentifrice composition.

Polyphosphates

The dentifrice composition can comprise polyphosphate. The polyphosphatecan be provided by a polyphosphate source. A polyphosphate source cancomprise one or more polyphosphate molecules. Polyphosphates are a classof materials obtained by the dehydration and condensation oforthophosphate to yield linear and cyclic polyphosphates of varyingchain lengths. Thus, polyphosphate molecules are generally identifiedwith an average number (n) of polyphosphate molecules, as describedbelow. A polyphosphate is generally understood to consist of two or morephosphate molecules arranged primarily in a linear configuration,although some cyclic derivatives may be present.

Preferred polyphosphates are those having an average of two or morephosphate groups so that surface adsorption at effective concentrationsproduces sufficient non-bound phosphate functions, which enhance theanionic surface charge as well as hydrophilic character of the surfaces.Preferred in this invention are the linear polyphosphates having theformula: XO(XPO₃)_(n)X, wherein X is sodium, potassium, ammonium, or anyother alkali metal cations and n averages from about 2 to about 21.Alkali earth metal cations, such as calcium, are not preferred becausethey tend to form insoluble fluoride salts from aqueous solutionscomprising a fluoride ions and alkali earth metal cations. Thus, thedentifrice compositions disclosed herein can be free of or substantiallyfree of calcium pyrophosphate.

Some examples of suitable polyphosphate molecules include, for example,pyrophosphate (n=2), tripolyphosphate (n=3), tetrapolyphosphate (n=4),sodaphos polyphosphate (n=6), hexaphos polyphosphate (n=13), benephospolyphosphate (n=14), hexametaphosphate (n=21), which is also known asGlass H. Polyphosphates can include those polyphosphate compoundsmanufactured by FMC Corporation, ICL Performance Products, and/orAstaris.

The dentifrice composition can comprise from about 0.01% to about 15%,from about 0.1% to about 10%, from about 0.5% to about 5%, from about 1to about 20%, or about 10% or less, by weight of the dentifricecomposition, of the polyphosphate source.

Humectants

The dentifrice composition can comprise a humectant, have low levels ofa humectant, or be free of a humectant. Humectants serve to add body or“mouth texture” to an oral care composition or dentifrice as well aspreventing the dentifrice from drying out. Suitable humectants includepolyethylene glycol (at a variety of different molecular weights),propylene glycol, glycerin (glycerol), erythritol, xylitol, sorbitol,mannitol, butylene glycol, lactitol, hydrogenated starch hydrolysates,and/or mixtures thereof. The dentifrice composition can comprise one ormore humectants each at a level of from 0 to about 70%, from about 5% toabout 50%, from about 10% to about 60%, or from about 20% to about 80%,by weight of the dentifrice composition.

Surfactants

The dentifrice composition can comprise one or more surfactants. Thesurfactants can be used to make the compositions more cosmeticallyacceptable. The surfactant is preferably a detersive material whichimparts to the composition detersive and foaming properties. Suitablesurfactants are safe and effective amounts of anionic, cationic,nonionic, zwitterionic, amphoteric and betaine surfactants, such assodium lauryl sulfate, sodium lauryl isethionate, sodium lauroyl methylisethionate, sodium cocoyl glutamate, sodium dodecyl benzene sulfonate,alkali metal or ammonium salts of lauroyl sarcosinate, myristoylsarcosinate, palmitoyl sarcosinate, stearoyl sarcosinate and oleoylsarcosinate, polyoxyethylene sorbitan monostearate, isostearate andlaurate, sodium lauryl sulfoacetate, N-lauroyl sarcosine, the sodium,potassium, and ethanolamine salts of N-lauroyl, N-myristoyl, orN-palmitoyl sarcosine, polyethylene oxide condensates of alkyl phenols,cocoamidopropyl betaine, lauramidopropyl betaine, palmityl betaine,sodium cocoyl glutamate, and the like. Sodium lauryl sulfate is apreferred surfactant. The dentifrice composition can comprise one ormore surfactants each at a level from about 0.01% to about 15%, fromabout 0.3% to about 10%, or from about 0.3% to about 2.5%, by weight ofthe dentifrice composition.

Thickening Agents

The dentifrice composition can comprise one or more thickening agents.Thickening agents can be useful in the dentifrice compositions toprovide a gelatinous structure that stabilizes the toothpaste againstphase separation. Suitable thickening agents include polysaccharides,polymers, and/or silica thickeners. Some non-limiting examples ofpolysaccharides include starch; glycerite of starch; gums such as gumkaraya (sterculia gum), gum tragacanth, gum arabic, gum ghatti, gumacacia, xanthan gum, guar gum and cellulose gum; magnesium aluminumsilicate (Veegum); carrageenan; sodium alginate; agar-agar; pectin;gelatin; cellulose compounds such as cellulose, carboxymethyl cellulose,hydroxyethyl cellulose, hydroxypropyl cellulose, hydroxymethylcellulose, hydroxymethyl carboxypropyl cellulose, methyl cellulose,ethyl cellulose, and sulfated cellulose; natural and synthetic clayssuch as hectorite clays; and mixtures thereof.

The thickening agent can comprise polysaccharides. Polysaccharides thatare suitable for use herein include carageenans, gellan gum, locust beangum, xanthan gum, carbomers, poloxamers, modified cellulose, andmixtures thereof. Carageenan is a polysaccharide derived from seaweed.There are several types of carageenan that may be distinguished by theirseaweed source and/or by their degree of and position of sulfation. Thethickening agent can comprise kappa carageenans, modified kappacarageenans, iota carageenans, modified iota carageenans, lambdacarrageenan, and mixtures thereof. Carageenans suitable for use hereininclude those commercially available from the FMC Company under theseries designation “Viscarin,” including but not limited to Viscarin TP329, Viscarin TP 388, and Viscarin TP 389.

The thickening agent can comprise one or more polymers. The polymer canbe a polyethylene glycol (PEG), a polyvinylpyrrolidone (PVP),polyacrylic acid, a polymer derived from at least one acrylic acidmonomer, a copolymer of maleic anhydride and methyl vinyl ether, acrosslinked polyacrylic acid polymer, of various weight percentages ofthe dentifrice composition as well as various ranges of averagemolecular ranges.

The thickening agent can comprise inorganic thickening agents. Somenon-limiting examples of suitable inorganic thickening agents includecolloidal magnesium aluminum silicate, silica thickeners. Useful silicathickeners include, for example, include, as a non-limiting example, anamorphous precipitated silica such as ZEODENT® 165 silica. Othernon-limiting silica thickeners include ZEODENT® 153, 163, and 167, andZEOFREE® 177 and 265 silica products, all available from EvonikCorporation, and AEROSIL® fumed silicas.

The dentifrice composition can comprise from 0.01% to about 15%, from0.1% to about 10%, from about 0.2% to about 5%, or from about 0.5% toabout 2% of one or more thickening agents.

Chelant

The dentifrice composition can comprise one or more chelants, having amolecular weight (MW) of less than 1000. The term “chelant”, as usedherein means a bi- or multidentate ligand having at least two groupscapable of binding to the divalent metal ions. Typically, those chelantsuseful herein will also form water soluble complexes with the stannousions. Dentifrice compositions comprising silica abrasives typicallyinclude one or more chelants to reversibly bind the tin ions to preventthe tin ions from irreversibly binding to the surface of silicaparticles. Suitable chelants herein include C₂-C₆ dicarboxylic andtricarboxylic acids, such as succinic acid, malic acid, tartaric acidand citric acid; C₃-C₆ monocarboxylic acids substituted with hydroxyl,such as gluconic acid; picolinic acid; amino acids such as glycine;phytic acid, salts thereof and mixtures thereof. Preferably, the chelantis sodium gluconate or a salt of citric acid.

The dentifrice composition can comprise one or more chelants each at alevel of from about 0.01% to about 5%, from about 0.2% to about 2%, fromabout 0.5% to about 1.5%, or from about 1% to about 3%, by weight of thedentifrice composition. Alternatively, the dentifrice composition can besubstantially free of, essentially free of, or free of a chelant becausethe dentifrice compositions of the present invention comprises a calciumabrasive instead of a silica abrasive. Additionally, the dentifricecomposition can comprise one or more chelants each at a level of lessthan about 1%, less than about 0.5%, less than about 0.1%, or less thanabout 0.01%, by weight of the dentifrice composition.

Other Ingredients

The dentifrice composition can comprise a variety of other ingredients,such as flavoring agents, sweeteners, colorants, preservatives,buffering agents, or other ingredients suitable for use in oral carecompositions, as described below.

Flavoring agents also can be added to the dentifrice composition.Suitable flavoring agents include oil of wintergreen, oil of peppermint,oil of spearmint, clove bud oil, menthol, anethole, methyl salicylate,eucalyptol, cassia, 1-menthyl acetate, sage, eugenol, parsley oil,oxanone, alpha-irisone, marjoram, lemon, orange, propenyl guaethol,cinnamon, vanillin, ethyl vanillin, heliotropine, 4-cis-heptenal,diacetyl, methyl-para-tert-butyl phenyl acetate, and mixtures thereof.Coolants may also be part of the flavor system. Preferred coolants inthe present compositions are the paramenthan carboxyamide agents such asN-ethyl-p-menthan-3-carboxamide (known commercially as “WS-3”) orN-(Ethoxycarbonylmethyl)-3-p-menthanecarboxamide (known commercially as“WS-5”), and mixtures thereof. A flavor system is generally used in thecompositions at levels of from about 0.001% to about 5%, by weight ofthe dentifrice composition. These flavoring agents generally comprisemixtures of aldehydes, ketones, esters, phenols, acids, and aliphatic,aromatic and other alcohols.

Sweeteners can be added to the oral care composition to impart apleasing taste to the product. Suitable sweeteners include saccharin (assodium, potassium or calcium saccharin), cyclamate (as a sodium,potassium or calcium salt), acesulfame-K, thaumatin, neohesperidindihydrochalcone, ammoniated glycyrrhizin, dextrose, levulose, sucrose,mannose, sucralose, stevia, and glucose.

Colorants can be added to improve the aesthetic appearance of theproduct. Suitable colorants include without limitation those colorantsapproved by appropriate regulatory bodies such as the FDA and thoselisted in the European Food and Pharmaceutical Directives and includepigments, such as TiO₂, and colors such as FD&C and D&C dyes.

Preservatives also can be added to the oral care compositions to preventbacterial growth. Suitable preservatives approved for use in oralcompositions such as methylparaben, propylparaben, benzoic acid, andsodium benzoate can be added in safe and effective amounts.

Titanium dioxide may also be added to the present composition. Titaniumdioxide is a white powder which adds opacity to the compositions.Titanium dioxide generally comprises from about 0.25% to about 5%, byweight of the dentifrice composition.

Other ingredients can be used in the oral care composition, such asdesensitizing agents, healing agents, other caries preventative agents,chelating/sequestering agents, vitamins, amino acids, proteins, otheranti-plaque/anti-calculus agents, opacifiers, antibiotics, anti-enzymes,enzymes, pH control agents, oxidizing agents, antioxidants, and thelike.

Ion Availability

The dentifrice composition can be described by its tin ion availabilityand/or its fluoride ion availability. The dentifrice composition canhave a tin ion availability at least about 70%, at least about 75%, atleast about 80%, or at least about 85% immediately after mixing, afterat least 1 month, after at least two months, or after at least 3 monthsusing an accelerated stability measurement at 40° C. The dentifricecomposition can have a fluoride ion availability of at least about 70%,at least about 75%, at least about 80%, or at least about 85%immediately after mixing, after at least 1 month, after at least twomonths, or after at least 3 months using an accelerated stabilitymeasurement at 40° C. 1 month of storage at 40° C. is equivalent to atleast 8 months of storage at room temperature (˜22-23° C.).

EXAMPLES

The invention is further illustrated by the following examples, whichare not to be construed in any way as imposing limitations to the scopeof this invention. Various other aspects, modifications, and equivalentsthereof which, after reading the description herein, may suggestthemselves to one of ordinary skill in the art without departing fromthe spirit of the present invention or the scope of the appended claims.

Experimental Methods

Tin Ion Availability

This method is suitable for determination of soluble tin in oral caretoothpaste or dentifrice compositions from about 5 to about 5,000 ppm Snin the aqueous slurry supernatant. The slurry was prepared by mixing 1part toothpaste with 3 parts water. An aliquot of slurry was aciddigested, diluted, and analyzed by inductively coupled plasma opticalemission spectrometry (ICP-OES) for each toothpaste measured. Resultsare reported here as ppm in the neat aqueous phase of the toothpasteand/or dentifrice.

Several standards and reagents were prepared prior to the beginning ofthe analysis. A 5% hydrochloric acid/5% Nitric acid rinse solution wasprepared by transferring 100 mL each of concentrated HCl andconcentrated HNO₃ using a graduated cylinder to a 2 L volumetric flaskcontaining about 1 L of ultrapure, 18 MΩ (DI) water. The solution wasswirled to mix and diluted to the mark of the graduated flask then mixedwell by repeated flask inversion.

A 1000 mg/L tin and 1000 mg/L gallium standard solution were purchased(Sigma Aldrich, Merck KGaA, Darmstadt, Germany) for preparation of thestandard solutions according to TABLE 1. A pipet was used to transferaccurate quantities of the standards to a 50 mL volumetric flask while agraduated cylinder was used for the concentrated acids. After transfer,the volumetric flask was filled to the line with DI water and mixedwell.

TABLE 1 Soluble Sn Standard Solution Compositions Conc HNO₃ Conc HCL1000 mg/L Sn 1000 mg/L Ga Solution (mL) (mL) Std (mL) Std (mL) Cal Blank2.5 2.5 0 0.2 Cal 10 mg/L Sn 2.5 2.5 0.5 0.2 LLOQ 0.5 2.5 2.5 0.025 0.2mg/L Sn QC 5 mg/L Sn 2.5 2.5 0.25 0.2

Slurries were prepared by weighing 2.00 grams of sample into a taredround bottom 38 mL centrifuge tube containing 10 glass beads. The weightwas recorded to a minimum of 0.001 g. Immedicably before slurrying, 6.0mL of DI water was transferred to the tubes. Tubes were capped andplaced on a vortexer, mixing the samples for 60 minutes at 1200 rpm. Thetubes were removed from the vortexer immediately following completion ofthe mixing cycle and placed in a centrifuge. They were centrifuged at21,000 relative centrifugal force (RCF) for 10 minutes. Immediatelyfollowing completion of centrifugation, the tubes were removed, and thesupernatant was gently mixed by inverting slowly three times making surethe solid plug at the bottom of the centrifuge tube was not disturbedbefore the sample was decanted. The supernatant was then decanted into a15 mL screw cap sample tube, making sure most of the supernatant wastransferred.

The supernatant samples were then digested by accurately weighing (to0.001 g) a 0.5 mL aliquot of supernatant into a 50 mL Falcon tube. Then2.5 mL of concentrated HCl and HNO₃ were added. The tubes were coveredwith a polypropylene watch glass and placed in a preheated blockdigester at 90° C. for 30 minutes. The samples were removed the from theheat, the watch class was rinsed three times with DI water (with about 1mL each time), and that rinsate was added to the digested supernatant.The gallium standard (0.2 mL) was pipetted into the digested supernatantand then the supernatant samples were diluted to 50 mL with DI water.The tubes were capped and mixed. A digestion method blank was preparedin the same manner using 0.5 mL of DI water instead of supernatant. Amethod blank was prepared and analyzed for each set of hot blockdigestions if more samples were prepared than could fit into the hotblock at once.

The ICP-OES (Perkin-Elmer 8300, Waltham, MA, USA) was operated by atrained and qualified operator with demonstrated capability of runningthe instrument and accurately determining the quantity of tin in oralcare compositions. The ICP-OES operation parameters were selected basedon the model and configuration according to the manufacturer'sinstructions. Samples were analyzed according to the following protocol:

-   -   1. The ICP-OES was preheated and optimized according to the        manufacturer's guidelines. Recommended system checks were        performed. The system was conditioned for 30 minutes prior to        analysis by running the HCl/HNO₃ rinse solution through the        sample introduction system.    -   2. The method for determining tin using a gallium internal        standard at the manufacturer recommended wavelengths,        integration times, and observation modes was loaded into the        operating computer.    -   3. The 5% HCl/5% HNO₃ rinse solution was used to rinse the        sample introduction system between the analysis of each blank,        standard, or test solution.    -   4. Three to five readings were recorded for all solutions during        analysis.    -   5. The calibration blank was analyzed.    -   6. The 10 ppm Sn standard was measured.    -   7. The 5 ppm Sn standard was measured.    -   8. The 0.5 ppm LLOQ tin standard was measured.    -   9. The method blank was measured.    -   10. The test solutions were measured.    -   11. The 5 ppm Sn standard was re-measured after every sixth test        solution and after the last sample. Enough standard was made to        complete the analysis.    -   12. The 0.5 ppm LLOQ tin standard was measured at the end of the        sample analysis.        The analysis was considered successful if the % relative        standard deviation of the replicate readings for the 10 ppm and        the 5 ppm tin standards was less than about 3%. The 5-ppm check        standard was within 96-104% of its value. The LLOQ was within        75-125% of its value. The method blank showed less tin signal        intensity than the LLOQ sample. The recovery of the internal        standard in each analyzed solution was within 90-130% of its        value.

The soluble tin was determined according to the following formula:

$\begin{matrix}{{{Soluble}{Tin}{in}{Composition}} = {\frac{\begin{matrix}{{Sn}{from}{ICP}\left( \frac{µg}{mL} \right) \times} \\{{Final}{volume}{of}{test}{solution}({mL})}\end{matrix}}{{Supernatant}{Weight}(g)}.}} & {{FORMULA}I}\end{matrix}$Results here are reported as a percentage of the as added Sn.Fluoride Ion Availability

Formulations A-E were stored at 40° C. in an accelerated stabilityexperiment. Samples of each formulation were analyzed at 1, 2, and/or 3months. Samples stored at 40° C. for 1 month would be expected toapproximate an equivalent sample stored for at least 8 months at roomtemperature (˜22-23° C.).

The fluoride ion availability was determined by making a 1:3 slurry ofthe selected dentifrice composition in water (1 part paste plus 3 partswater). The dentifrice slurries were centrifuged, and the supernatantwas isolated. Equal parts of dentifrice supernatant and ionic strengthadjuster buffer TISAB IV (RICCA, Cat #8673-32) were mixed in a separatecontainer. The concentration of fluoride ions were measured with afluoride ion selective electrode (VWR Symphony, Cat #14002-788) byconverting millivolt values to concentration of fluoride ions relativeto a calibration curve of standard fluoride ion concentration.

TABLE 2 shows the dentifrice compositions tested. Formulas A and B areinventive examples, which have a calcium abrasive, calcium carbonate.Formula A is a low water dentifrice composition and includes stannouschloride as the tin ion source. Formula B is an anhydrous dentifricecomposition and includes stannous fluoride as the tin ion source.

Formulations C, D, and E are comparative examples, which have a silicaabrasive, hydrated silica. Formulations C, D, and E are low to moderatedentifrice compositions with a combination of stannous fluoride andstannous chloride as an additional tin ion source due to the expectedlow tin ion availability based on the interactivity between the silicaabrasive and tin ions in solution.

TABLE 2 Dentifrice Compositions Ingredient A (wt %) B (wt %) C (wt %) D(wt %) E (wt %) SnF₂ — 0.45 0.45 0.45 0.45 SnCl₂ ^(a) 0.55 — 0.56 0.560.56 Water 16.30 — 24.05 22.75 18.48 CaCO₃ 32.00 30.00 — — — HydratedSilica — — 17.50 17.50 17.50 Glycerin — 33.70 — — — PEG 600 — 6.00 — — —Sorbitol 10.86 — 46.00 46.00 46.00 Erythritol 20.00 20.00 — — —Pyrophosphate^(b) — — — — 3.17 Glass H — 5.00 — — — Na Gluconate 1.000.65 — 1.30 — SLS^(c) 1.30 1.20 — — — SLS^(d) — — 4.60 4.60 4.60 Urea5.00 — — — — Botanical blend 0.50 — — — — NaOH^(e) 0.33 — 1.40 1.40 3.80Na₃PO₄ — 0.50 — — — NaHCO₃ 10.00 — — — — Saccharin 0.50 0.25 0.50 0.500.50 Sucralose — — 0.06 0.06 0.06 TiO₂ — 0.50 0.50 0.50 0.50 Flavor 1.001.00 1.00 1.00 1.00 Silica Z-165^(f) — — 1.00 1.00 1.00 Carrageenan 0.44— 1.50 1.50 1.50 Xanthan Gum 0.22 — 0.88 0.88 0.88 Carbomer^(g) — 0.75 —— — ^(a)SnCl₂ with 10% w/w silica; ^(b)Sodium acid pyrophosphate(Na₂H₂P₂O₇); ^(c)SLS powder; ^(d)SLS solution 28% w/w in water; ^(e)NaOHsolution 50% w/w in water; ^(f)Thickening silica ZEODENT ® 165;^(g)Carbopol ® 956

TABLE 3 Available Tin Ions during Accelerated Stability at 40° C. forFormula A Soluble Sn Duration (% theoretical) Slurry p Initial 85 8.61 1month 83 8.65 3 months 81 8.67

TABLE 3 shows the percent available tin ions after an acceleratedstability study for Formula A. Initially, Formula A had a slurry pH of8.61 and 85% of the theoretical tin ion amount, or the amount of tinions added to the composition. The tin ion availability dropped to 83%and 81% after 1 and 3 months, respectively, after being stored at 40° C.Storage of the compositions at 40° C. for 1 month is expected to projectthe stability of the composition at room temperature (˜22-23° C.) for atleast 8 months. Thus, tin ions are stable in compositions comprising acalcium abrasive, such as calcium carbonate, for at least 24 months ifstored at room temperature (˜22-23° C.).

TABLE 4 Available Tin Ions during Accelerated Stability at 40° C. forFormula B Soluble Sn Soluble F Duration (% theoretical) (% theoretical)Slurry pH Initial 83.2 93 7.38 1 month 85.0 84 7.40 2 months 86.4 847.44 3 months 96.5 85 7.47

TABLE 4 shows the percent available tin ions and available fluoride ionsafter an accelerated stability study for Formula B. Initially, Formula Bhad a slurry pH of 7.38 and 83% the theoretical tin ion amount, or theamount of tin ions added to the composition. The tin ion availabilitywas 85%, 86%, and 97% after 1, 2, and 3 months, respectively, which, asdescribed above, would project to be 8, 16, and 24 months at roomtemperature (˜22-23° C.). Thus, tin ions are stable in compositionscomprising a calcium abrasive, such as calcium carbonate.

Initially, Formula B had 93% of the theoretical fluoride ion amount, orthe amount of fluoride ions added to the composition. The fluoride ionavailability was 84%, 84%, and 85% after 1, 2, and 3 monthsrespectively. Thus, fluoride ions are unexpectedly stable incompositions comprising a calcium abrasive, such as calcium carbonate.

TABLE 5 Available Tin Ions during Accelerated Stability at 40° C. forFormula C-E Formula C Formula D Formula E Available Available AvailableSn (% Slurry Sn (% Slurry Sn (% Slurry Duration theoretical) pHtheoretical) pH theoretical) pH Initial 30.29 8.16 39.04 8.00 64.01 9.181 month 18.38 8.26 23.64 8.10 42.59 9.14 2 months 17.68 8.16 19.33 8.0036.31 9.12

TABLE 5 shows the percent available tin ions after an acceleratedstability study for Formula C, D, and E. Initially, Formula C had aslurry pH of 8.18 and 30% of the theoretical tin ion amount, or theamount of tin ions added to the composition. The tin ion availabilitywas 18% and 18% after 1 month and 2 months, respectively. Initially,Formula D had a slurry pH of 8.00 and 39% the theoretical tin ionamount, or the amount of tin ions added to the composition. The tin ionavailability was 24% and 19% after 1 month and 2 months, respectively.Initially, Formula E had a slurry pH of 9.18 and 64% the theoretical tinion amount, or the amount of tin ions added to the composition. The tinion availability was 43% and 36% after 1 month and 2 months,respectively. As shown in TABLE 5, there was a significant loss of tinions even at room temperature (initial values). The loss of tin ionscontinued after 1 month at 40 C. The relatively higher values forFormula D and E are due to better binding of tin ions by the chelantsgluconate and pyrophosphate, which help minimize reactivity with silicaand stabilize the tin ions against oxidation and hydrolysis by bondingwith tin ions.

Importantly, the tin ion availability was much higher in compositionscomprising a calcium carbonate abrasive, i.e. Formula A and Formula B,than in compositions comprising a silica abrasive, i.e. Formula C-E.TABLE 3 and TABLE 4 show tin ion availabilities of at least about 80% ofthe theoretical tin ion amount. In contrast, Formula C-E only had tinion availabilities of from 18% to 36% of the theoretical tin amountafter two months of accelerated stability at 40° C. Thus, replacing asilica abrasive with a calcium carbonate abrasive can improve the tinion availability by as much as 450% (from 18% to 86%). Thus, thefindings in TABLE 2-5 demonstrated that stannous ions are chemicallystable at a pH of greater than 7 when combined with a calcium abrasive.Additionally, stannous ions are non-reactive to calcium abrasives, suchas calcium carbonate, unlike with silica abrasives. Specifically, theresults in TABLE 3 & 4 indicated that stannous ions are unexpectedlystability in compositions comprising calcium carbonate.

While it was expected that interactions between the calcium ions from acalcium abrasive would react with and diminish the amount of availablefluoride ions from a fluoride ion source, Formula B, which comprisescalcium carbonate and stannous fluoride, had a fluoride ion availabilityof 93% initially and 85% after 3 months of accelerated stability at 40°C.

The dimensions and values disclosed herein are not to be understood asbeing strictly limited to the exact numerical values recited. Instead,unless otherwise specified, each such dimension is intended to mean boththe recited value and a functionally equivalent range surrounding thatvalue. For example, a dimension disclosed as “40 mm” is intended to mean“about 40 mm.”

Every document cited herein, including any cross referenced or relatedpatent or application and any patent application or patent to which thisapplication claims priority or benefit thereof, is hereby incorporatedherein by reference in its entirety unless expressly excluded orotherwise limited. The citation of any document is not an admission thatit is prior art with respect to any invention disclosed or claimedherein or that it alone, or in any combination with any other referenceor references, teaches, suggests or discloses any such invention.Further, to the extent that any meaning or definition of a term in thisdocument conflicts with any meaning or definition of the same term in adocument incorporated by reference, the meaning or definition assignedto that term in this document shall govern.

While particular embodiments of the present invention have beenillustrated and described, it would be obvious to those skilled in theart that various other changes and modifications can be made

without departing from the spirit and scope of the invention. It istherefore intended to cover in the appended claims all such changes andmodifications that are within the scope of this invention.

What is claimed is:
 1. A dentifrice composition comprising: (a) stannouschloride; (b) calcium abrasive; and (c) from about 5% to about 45%, byweight of the composition, of water, wherein the dentifrice compositionhas a pH of greater than
 7. 2. The dentifrice composition of claim 1,wherein the calcium abrasive comprises calcium carbonate.
 3. Thedentifrice composition of claim 1, wherein the composition compriseszinc.
 4. The dentifrice composition of claim 3, wherein the zinccomprises zinc lactate, zinc oxide, zinc phosphate, zinc chloride, zincacetate, zinc hexafluorozirconate, zinc sulfate, zinc tartrate, zincgluconate, zinc citrate, zinc malate, zinc glycinate, zincpyrophosphate, zinc metaphosphate, zinc oxalate, zinc carbonate, orcombinations thereof.
 5. The dentifrice composition of claim 1, whereinthe composition comprises silica abrasive.
 6. The dentifrice compositionof claim 1, wherein the composition is free of silica abrasive.
 7. Thedentifrice composition of claim 1, wherein the composition compriseshumectant.
 8. The dentifrice composition of claim 7, wherein thehumectant comprises glycerin, sorbitol, erythritol, xylitol, butyleneglycol, propylene glycol, polyethylene glycol, or combinations thereof.9. The dentifrice composition of claim 1, wherein the dentifricecomposition comprises from about 0.01% to about 15%, by weight of thecomposition, surfactant.
 10. The dentifrice composition of claim 1,wherein the composition comprises thickening agent.
 11. The dentifricecomposition of claim 10, wherein the thickening agent comprises xanthangum, carrageenan, a polyethylene glycol, a crosslinked polyacrylic acidpolymer, polyvinyl pyrrolidone, fatty alcohols, or combinations thereof.12. The dentifrice composition of claim 1, wherein the compositioncomprises fluoride.
 13. The dentifrice composition of claim 12, whereinthe fluoride comprises sodium fluoride, stannous fluoride, sodiummonofluorophosphate, amine fluoride, zinc fluoride, or combinationsthereof.
 14. The dentifrice composition of claim 1, wherein thecomposition is free of fluoride.
 15. The dentifrice composition of claim1, wherein the calcium abrasive comprises calcium carbonate, calciumpyrophosphate, dicalcium phosphate, or combinations thereof.
 16. Thedentifrice composition of claim 1, wherein the composition comprisespolyphosphate.
 17. The dentifrice composition of claim 16, wherein thepolyphosphate comprises pyrophosphate, tripolyphosphate,tetrapolyphosphate, sodaphos poly-phosphate, hexaphos polyphosphate,benephos polyphosphate, hexametaphosphate, or combinations thereof. 18.The dentifrice composition of claim 1, wherein the composition is freeof polyphosphate.
 19. The dentifrice composition of claim 1, wherein thecomposition comprises from about 10% to about 45%, by weight of thecomposition, of water.
 20. The dentifrice composition of claim 1,wherein the dentifrice composition has about 70% or greater of availabletin ions after three months at 40° C.